Novel glass fabric buffer wheel



NOVEL GLASS FABRIC BUFFER WHEEL Filed Dec. 21, 1949 INVENITOR.Edwz'zzl.lofi

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WW TURKEY United States Patent fire latented Jan. 4, 1555 NovEL GLASSFABRIC BUFFER WHEEL Edwin L. Lotz, Nutley, N. 1., assignor, by mesneassignments, to Harvel Research Corporation, a corporation of New JerseyApplication December 21, 1949, Serial No. 134,285

2 Claims. (Cl. 512tl7) This invention relates to novel articles ofmanufacture and to methods for making them. More particularly thisinvention is directed to buffer wheels and especially to those of thehigh temperature type. In one of its more specific aspects the inventionis directed to novel fabrics finding especial application as butfingelements and being especially suitable for the polishing and buffing ofmetal objects and for the removal of solder flux and excess solder fromso called tin cans in the source of their manufacture.

Prior to this invention, it was the practice in the tin canmanufacturing industry to remove the excess molten solder and fiux whilestill hot from the cans during their manufacture by subjecting them tothe action of the periphery of a plurality of layer upon layer of cottonfabric secured to a rotating spindle. The primary disadvantage of suchbuffer wheels made up of said layers of cotton fabric was their shortlife, usually of 1-8 hours. The shortness of the life of the cottonfabric buffer wheels was due to the fact that when in contact with themolten materials, it either burned or charred in a short time. in normaloperations, therefore, due to the short life of such wheels, it becamenecessary to stop frequently the automatic can producing machinery sothat the cotton bufier wheels could be replaced.

It was in order to obivate, at least in part, the aforesaiddisadvantages that the present invention has been made. in the course ofexperimentation relative to this problem, i have discovered that I mayproduce buffer wheels and fabrics having the following advantages:

When employed layer upon layer and secured to a rotating spindle andapplied edgewise or periphery-wise to the molten or hot solder and fluxon cans in the course of their manufacture.

1. The bulfer will not burn or char;

2. The bufier will have a life of 50-70 hours of continuous operation;

3. The individual filaments separate from each other, upon theapplication of pressure, to provide a great number of individual minutefilaments giving a soft uniform wiping surface which is essential forthe desired bulfing action.

The aforesaid as well as other objects and advantages of the presentinvention may be apparent from the fOllO ing description taken togetherwith the appended drawings wherein:

Fig. 1 is a side view of a buffing wheel on a spindle, a part of whichis shown.

Fig. 2 is a top plan view of the construction shown in Fig. 1.

Fig. 3 is a top plan view of an annular individual sheet embodying theinvention.

As shown in the drawings there is a spindle l carrying a support plate11. Mounted on the support plate 11. and having an opening therethroughthrough which passes the outer end of the spindle It is a buffer 12which may be demountab v locked to the s indle by a top plate 13 and nut14. The buffer wheel 12 consists of a plurality of layers 15 of fabricor cloth laid flatwise layer on layer, using 5010() or more of saidlayers to provide a wheel 12 of the desired thickness. Each layer 15 isessentially a disc having a central opening therethrough. Generally thestack of discs 15 are held together by stitching 16 around the centralopening.

According to this invention, each of said discs 15 con:- prises a woventhread or yarn fabric, having a thread or yarn count in the range of 40x to 90 x 60 and preferably x 58 per square inch, with each yarn orthread containing glass filaments in the count range of 150-408. Such aglass cloth is treated to impregnate the individual filaments with aresin which acts as a binder between thefilaments of the yarn but doesnot fill the interstices between the yarns of the cloth. For thispurpose of the invention there is employed an alkyl phenyl polysiloxane,and the alkyl group may be methyl, ethyl, propyl, etc. These resins arecapable of remaining flexible and nonhardening at 500 F. over a one hourperiod. are capable of bind ng the filaments to each other and tomaintain this binding action for a period of one hour at 509 F.

The resin may be coupled with the cloth by passing the glass cloththrough a solution or dispersion of the binder in a solvent. Then theloaded glass cloth is passed through pressure rolls to control theamount of said solution in the cloth and following this step the solventis driven off to partially set the resin deposited between theindividual filaments. In this manner, the individual varns areimpregnated to coat the individual filaments thereof with said resinwhich acts as a binder between the filaments, but does not fill theinterstices between the yarns of the fabric. The finished fabric is nowout to provide discs 15.

One of the methods which may be employed to obtain the resin impregnatedfabric is to pass a length of said glass cloth fabric through a solutionof an alkyl phenyl polysiloxane which is normally liquid and examples ofv/ .ich are those ap earing on the market as solutions of the DowCorning Corporation under the names of DC 996 Silicone Varnish and DC993 Silicone Varnish, both of which are usually 50% solutions of methylphenyl polysiloxane in toluene. For my purposes the solutions are firstdiluted to approximately 25% solids by adding suificient toluene orxylol and it is through such diluted solutions that the fabric ispassed. Then the impregnated fabric is wiped with a doctor andsubsequently maintained at a temperature of 300-325 F. for about 15-2Qminutes whereupon the solvent has been substantially driven off and theresin has been converted from the normally liquid to a tough,non-brittle gel. The amount of resin in said fabric measures in therange of about .5-2 ounces per square yard of fabric.

Another method which may be emploved is to provide a. dispersion of oneof said solutions DC 996 Silicone Varnish or DC 993 Silicone Varnish inwater. Such dispersions are made up in the proportion of 150 grams ofwater, grams of one of said solutions and 5-l0 grams of a dispersingagent which may be made up of 5 ams of morpholine and 5 grams of oleicacid. The glass fabric may be passed through said dis ersion, wiped ordoctored, then maintained at 300-325 F. for 15-26 minutes to drive offthe water, solvent and dispersin agent and to convert the resin to atough gel which is not brittle and measuring .5-2 ounches per squareyard of fabric.

By whatever method employed, the resin is substantially uniform ydistributed throughout said fabric and between the filaments of theyarns or hreads there f to act as a binder therebetween wi hout fillingthe voids or interstices between the yarns or threads.

The resin containing fabric is now cut into discs 35 and these discs areassembled in the manner shown in Fig. l of the drawings. The bufferwheel 12 so produced is mounted on the spindle as shown. The combinationis rotated and the tin cans containing the solder and flux are moved inthe path of the rotating bulfer wheel 15. The outer or the free orwiping ends of the yarns or threads on contact with the hot solder willhave the ends of the filaments thereof move away from each other whereban end brushin effect is obtained. The presence of said binders even inthe limited amounts herein recited, permit the attainment of this effectand at the same time the remainder of the lengths of the filament arekept from coming apart due to the presence of the binder. in actualcommercial practice bufier wheels of my novel fabrics have been farsuperior in both performance and life when compared with those of cottonwhich had been used commercially heretofore for that purpose.

These fabrics have served as excellent bufier wheel materials,especially in the tin can art to wipe off the excess hot solder andflux. Upon application of pressure, as

7 rubbing against the surface of the metal, the ends of the individualfilaments of the yarns separate from one another to provide a softuniform wiping surface which is necessary for bufiing wheels.

While this invention has been described in detail, it is not to belimited thereby because various changes and modifications may be madewithin the spirit thereof.

Having thus described my invention, what I claim is:

1. A novel buffer comprising a plurality of approximately disc-shapedlayers laid fiatwise oneon the other and secured together with eachlayer comprising a woven glass fabric having a count in the range of 40x 30 to 90 X 60, said fabric comprising yarn containing from 150 408individual glass filaments, and alkyl phenyl polysiloxane resinousbinder for saidfilaments, the quantity of said binder in said fabricbeing in the proportion of .5-2

7 ounces of binder to 1 square yard of said fabric.

4 2. A novel bufier as defined in claim 1 with said alkyl phenylpolysiloxane being methyl phenyl polysiloxane.

. References Cited in the file of this patent UNITED 'STATES PATENTS1,737,574 Divine Dec. 3, 1929 2,215,061 Alt Sept. 17, 1940 2,390,370Hyde Dec. 4, 1945 2,392,805 7 Biefeld Jan. 15, 1946 2,449,572 WelshSept. 21, 1948 2,492,498 Pedersen Dec. 27, 1949 2,494,920 Warrick Jan.17, 1950 2,530,635 Sowa Nov. 21, 1950

